Low-level laser therapy comprises a high-intensity light that is focused into a single light energy beam. With low-level laser therapy, a clinician can potentially shrink or destroy tumors by exposing them to the wavelengths of light from a laser and excising cancerous tissue. Laser therapy is often used for more superficial growths appearing on the surface of the skin or in the lining of internal organs, as opposed to free radicals and tumors appearing in deeper tissues.

Along with direct treatment for cancer, laser therapy can be used to combat cells contributing to precancerous growths, like colon polyps, or as a treatment for relieving certain symptoms or removing obstructions.

Compared to chemotherapy, radiation, and surgery, laser therapy is a minimally invasive procedure used to treat chronic conditions. For cancerous tissue in the lining of internal organs, laser therapy can be administered through the use of an endoscope that is inserted via an opening in the body to then transmit wavelengths of light. Optical fibers fixed to the end of the endoscope can then cut or destroy any internal tumors that could be lending to pain and inflammation or maybe affecting blood circulation.

Laser-induced interstitial thermotherapy (LITT) is a form of laser therapy that is similar to hyperthermia. Through LITT, a laser heats cancerous tissue, raising the temperature enough to damage or destroy the tumor cells. This therapy treatment helps to shrink the tumor without causing harm to healthy tissue nearby.

Sources:

https://www.cancer.gov/about-cancer/treatment/types/surgery/lasers-fact-sheet